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Full-Text Articles in Chemistry
On The Ability Of Pnicogen Atoms To Engage In Both Σ And Π-Hole Complexes. Heterodimers Of Zf2C6H5 (Z = P, As, Sb, Bi) And Nh3, Wiktor Zierkiewicz, Mariusz Michalczyk, Rafał Wysokiński, Steve Scheiner
On The Ability Of Pnicogen Atoms To Engage In Both Σ And Π-Hole Complexes. Heterodimers Of Zf2C6H5 (Z = P, As, Sb, Bi) And Nh3, Wiktor Zierkiewicz, Mariusz Michalczyk, Rafał Wysokiński, Steve Scheiner
Chemistry and Biochemistry Faculty Publications
When bound to a pair of F atoms and a phenyl ring, a pyramidal pnicogen (Z) atom can form a pnicogen bond wherein an NH3 base lies opposite one F atom. In addition to this σ-hole complex, the ZF2C6H5 molecule can distort in such a way that the NH3 approaches on the opposite side to the lone pair on Z, where there is a so-called π-hole. The interaction energies of these π-hole dimers are roughly 30 kcal/mol, much larger than the equivalent quantities for the σ-hole complexes, which are only 4–13 kcal/mol. On …
Interactions Of (My) 6 (M = Zn, Cd; Y = O, S, Se) Quantum Dots With N-Bases, Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner
Interactions Of (My) 6 (M = Zn, Cd; Y = O, S, Se) Quantum Dots With N-Bases, Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner
Chemistry and Biochemistry Faculty Publications
(MY)6 clusters, with M = Zn and Cd and Y = O, S, Se, form double-layer drum-like structures containing M–Y covalent bonds. The positive regions near the M atoms attract the N atom of both NH3 and NMe3 so as to form a noncovalent M···N bond. This bond is quite strong, with interaction energies exceeding 35 kcal/mol. The bond strength diminishes with reduced electronegativity of the Y atom (O > S > Se) and is stronger for M = Zn than for Cd. Trimethylation of the base enhances the bond strength. The interaction is dominated by the electrostatic component …
Dual Geometry Schemes In Tetrel Bonds: Complexes Between Tf4(T = Si, Ge, Sn) And Pyridine Derivatives, Wiktor Zierkiewicz, Mariusz Michalczyk, Rafał Wysokiński, Steve Scheiner
Dual Geometry Schemes In Tetrel Bonds: Complexes Between Tf4(T = Si, Ge, Sn) And Pyridine Derivatives, Wiktor Zierkiewicz, Mariusz Michalczyk, Rafał Wysokiński, Steve Scheiner
Chemistry and Biochemistry Faculty Publications
When an N-base approaches the tetrel atom of TF4(T = Si, Ge, Sn) the latter moleculedeforms from a tetrahedral structure in the monomer to a trigonal bipyramid. The base can situateitself at either an axial or equatorial position, leading to two different equilibrium geometries.The interaction energies are considerably larger for the equatorial structures, up around 50 kcal/mol,which also have a shorter R(T··N) separation. On the other hand, the energy needed to deform thetetrahedral monomer into the equatorial structure is much higher than the equivalent deformationenergy in the axial dimer. When these two opposite trends are combined, it is the axial …